How to Fix the Gap in the Wood Furniture

Gaps and cracks are commonly problems found in the wood product. There are various reasons that could cause the gap or crack in the wood, that are: the unstable moisture content of the wood, the improper gluing, the improper construction, and too strong physical abuse. The crack or gap that is caused by the improper gluing and construction only happened at the joint. But the crack that is caused by the wood movement can be found anywhere. The wood with inappropriate moisture content will shrinkage or expand and cause gaps and cracks anywhere in the wood.
But if we find the gap or crack in the wood product that has been built, then we need to fix it. Fixing the gap in this step could be expensive, but we have to do it. The cracked wood product will look bad and seem like a broken product. 

crack at the finish product

 
 

Here is the step to fix the gap and crack in the wood product.

• Check the moisture content of wood. 

The first thing we need to do is check the wood moisture content. Make sure the wood moisture content is already stable as the standard should be. The unstable moisture content will lead to a wood movement that results in a crack, gap, or open joint at the wood. Any correction will be useless if the wood is still moving. If we find the wood moisture content is still too high (or too low), then we better let it sit for a few days to let the wood be stable before we do anything to fix it.

• Check the glue and construction.

The gap or crack at the joint indicates that the joint is not strong enough. If we find this problem, we need to check the glue quality and the construction. Make sure the product is properly constructed. The wood joint should have the tenon-mortise or dowel to get the strong connection.
Check the glue; make sure we have the perfect bond. If we find that the wood bond is not strong enough, we better detach the joint and reglue it with the proper process and product. 

• Insert a piece of wood at the gap.

After we find that there is no problem with the wood moisture content or construction, then we can start to fix the gap or crack. The best way to fix the gap (especially for the big size) is inserting wood to fill it. This wood will fill the gap with wood, giving it a natural appearance. The wood is also less shrinkage than the putty; it will give a stable, flat surface.
Take a small wood piece and shape it according to the gap or crack. Use wood pieces with the same color and type with the products. Apply glue to the wood piece and inside the gap. Insert the wood piece to fill the gap; let the glue dry. Then cut off and sand the protruding wood to get a flat surface and smooth surface.

• Apply putty.

The putty application is a fast process. However, the putty should only be used to fix the small crack, gap, or hole. The putty will result in an unnatural appearance and also tend to shrinkage when it finishes. But for small holes and gaps, the putty is the best choice to be used.
Choose putty with the same color as the wood. If necessary, we can add some pigment to the putty to match the color with the wood color. Apply the putty with a knife or scrap to fill the gap or crack. Let it dry and sand the wood putty to get a flat surface. See our previous article: wood putty

• Apply the fill-in stick.

It is a kind of putty that is designed to be applied to the finished product. It can only be used for the small gap or crack in small sizes and in the less exposed part, such as the leg, apron, or cabinet corner. It is not recommended to fix the top panel to the table that needs a good appearance. 
Choose the fill-in stick with the proper color, then insert the stick to fill the gap with a knife. Cut the protruding part with a knife. See our previous article: touch up kit for the furniture finishing